15.68 Ct. Cabochon Moonstone from Ceylon (Sri Lanka)

This listing from The Natural Gemstone Company describes a single, translucent orange moonstone of notable size and presence, weighing 15.68 carats, with dimensions of 19.13 by 13.94 by 8.67 millimeters, fashioned into an oval cabochon. The overall length to width ratio of 1.37 provides a balanced elongated silhouette that suits both classic and contemporary settings. The cutter executed a cabochon profile, emphasizing a broad, gently domed crown and a proportional pavilion that preserves the material weight while optimizing the stone s optical display. Clarity is graded as very slightly included at normal viewing distance, indicating minimal, non distracting internal features when evaluated with the unaided eye. Color is assessed as medium intense orange, with a warm peach to apricot tonal spectrum that remains even across the table. The polish is rated excellent, indicating a high gloss finish free from polish lines or surface abrasions, and there has been no enhancement applied to this specimen. Origin is Ceylon, Sri Lanka, a source renowned for feldspar materials with clean adularescence and warm hue variants.

From a lapidary and gemological perspective, the cabochon cut on this moonstone is purposeful and technically appropriate, given the mineralogical structure of moonstone as a potassium feldspar with interleaved lamellar twinning. The cabochon dome is calibrated to a depth of 8.67 millimeters, which allows light to interact with the thin transparent microlayers and produce the characteristic internal sheen without sacrificing translucency. Optical behavior in moonstone is governed by scattering and interference within these stacked layers, commonly described as adularescence, and the translucency of this piece permits a soft, broad glow rather than a sharp, pinpoint flash. Refractive index for potassium feldspar typically falls between 1.518 and 1.526, and specific gravity commonly ranges between 2.56 and 2.62, values that inform cutting resistance and setting engineering. Hardness on the Mohs scale is between 6 and 6.5, requiring mindful handling during setting and wear to avoid abrasion and impact damage.

Clarity assessment at eye level as very slightly included conveys that internal features are present but limited in size and distribution, and they do not interrupt the overall optical effect. Under 10 times magnification the stone reveals fine planar interfaces and occasional pinpoint inclusions oriented parallel to the cleavage planes, typical of natural orthoclase moonstone. These internal features can act to enhance the adularescent effect by providing additional scattering planes, when they are fine and well oriented, whereas larger fractures or clouding would diffuse light and weaken the phenomenon. The translucency in this specimen allows light to penetrate and interact with internal layering, giving depth to the color and producing a luminous core when light is directed across the dome. The excellent polish contributes to clean external reflection, allowing the internal adularescence to be observed without surface interference.

For design and setting considerations the dimensions and profile of this oval cabochon lend themselves well to bezel settings that protect the stone s girdle while showcasing the domed crown. The weight of 15.68 carats corresponds to approximately 3.136 grams, so the center of gravity and mass distribution should be accounted for in prong or hybrid mountings to prevent rotation in the setting. The 1.37 length to width ratio produces a visually pleasing elongation that flatters finger proportions when set in rings or provides an elegant focal point in pendants. Given the dome height, a slightly raised bezel or low profile bezel with internal seat relief will minimize stress on the cabochon during seat placement. When orienting the stone for maximum adularescence, position the table to receive broad, diffuse light across the dome so that the internal sheen appears as a central glow, rather than a narrow flash. Because this moonstone is untreated, the cutter s original weight and proportions should be preserved, and any setting should be reversible to maintain provenance and collector value.

Provenance from Ceylon, Sri Lanka, contributes to the market desirability of this orange moonstone, as Sri Lankan material is historically associated with fine color balance and clean, well defined adularescence. The absence of enhancement is an important attribute for connoisseurs and collectors, and it simplifies care and long term stability considerations. The Natural Gemstone Company performs standard gemological verification and quality control, and we can provide additional imaging or report documentation upon request to support appraisal and insurance needs. For jewelry designers and private collectors seeking a natural, technically well executed example of orange moonstone, this 15.68 carat oval cabochon presents a compelling combination of size, color intensity, workmanship, and natural origin. Please contact The Natural Gemstone Company for bespoke setting recommendations, conservation advice, or to arrange an appraisal, and our team will provide detailed guidance tailored to your design and technical specifications.